Towards full-colour tunable photoluminescence of monolayer MoS2/carbon quantum dot ultra-thin films
Towards full-colour tunable photoluminescence of monolayer MoS2/carbon quantum dot ultra-thin films
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DOI：
10.1039/c7tc01773a
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发表时间：
2017-06
影响因子：
6.4
通讯作者：
W. Su;Yuchan Wang;Weiwei Wu;Haiying Qin;Kaixin Song;Xiwei Huang;Lijie Zhang;Daqin Chen
中科院分区：
文献类型：
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作者：
W. Su;Yuchan Wang;Weiwei Wu;Haiying Qin;Kaixin Song;Xiwei Huang;Lijie Zhang;Daqin Chen
由于激子能量和能带结构的限制，单层（1 L）MoS 2只能发射窄带红光。在此，我们通过用高度发光的碳量子点（CQD）的超薄层涂覆1 L-MoS 2来绕过这一限制。这些新颖的1 L-MoS 2/CQD超薄膜具有多个发射带，包括属于MoS 2的红光带和属于CQD的可调谐带。通过将CQD的厚度优化至约10 nm，可以获得这些带的平衡强度。通过改变激发波长，这些1 L-MoS 2/CQD超薄膜的发射带可以从550-700 nm调制到450-700 nm，导致从橙子（CIE 0.5149，0.3766）到黄绿色（CIE 0.3175，0.4509）的可调谐光发射。这些可调谐的发射带比1 L-MoS 2的发射带宽得多。然而，迄今为止，在使用氧化石墨烯量子点（GOQD）或石墨烯量子点（GQD）制备的其他1 L-MoS 2/QD薄膜中尚未观察到这种全色可调谐发射。
Due to the limitations of excitonic energy and band structure, monolayer (1L) MoS2 can only emit a narrow band of red light. Herein, we bypassed this restriction by coating 1L-MoS2 with an ultra-thin layer of highly luminescent carbon quantum dots (CQDs). These novel 1L-MoS2/CQD ultra-thin films exhibit multiple emission bands, including red light bands belonging to MoS2 and tunable bands belonging to the CQDs. A balanced intensity of these bands can be obtained by optimizing the thickness of the CQDs to ∼10 nm. By varying the excitation wavelength, the emission band of these 1L-MoS2/CQD ultra-thin films can be modulated from 550–700 nm to 450–700 nm, resulting in tunable light emission from orange (CIE0.5149, 0.3766) to yellow-green (CIE0.3175, 0.4509). These tunable emission bands are much broader than those of 1L-MoS2. However, to date, this full-color tunable emission has not been observed in other 1L-MoS2/QD thin films prepared using graphene oxide quantum dots (GOQDs) or graphene quantum dots (GQDs).